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Electric Drivetrains
scootz - 17/12/17 at 10:53 AM

Guess its something we need to start looking at (assuming we're still allowed to build our own cars in 10 years time).

I thought it was out of reach for Seven type vehicles as the Tesla Roadster (Lotus chassis derived) was a porker, but seems Westfield did a decent job on their iRacer.

I know bugger all about electrics, but there are plenty clever folks on here, so how about we start pooling the knowledge!


coyoteboy - 17/12/17 at 12:50 PM

Yeah I think they're more likely to remove self build rights before we're forced to go all electric.

However motors and drive control are relatively easy, the difficulties in my view come from battery design, mass, safety and cost.


Schrodinger - 17/12/17 at 04:31 PM

Tiger had an electric 6 at one time around 2003/4 iirc.


David Jenkins - 17/12/17 at 04:39 PM

This is quite an interesting prospect that could (possibly) be installed in a Locost...
Bosch Powertrain

Of course, they don't say how much it would cost...


Slater - 17/12/17 at 05:46 PM

This chap built an electric Westfield in Barbados

good read here " The fastest accelerating Westfield in the world? The MegaWatt"

Linker to WSCC build blog

It includes some youtube clips too.


scootz - 17/12/17 at 09:54 PM

Cheers guys. Electric motors are appearing on eBay now at sensible money - if only getting them to work outside the OE application meaningfully was easy (and at similarly sensible money!).


craigdiver - 17/12/17 at 10:05 PM

quote:
Originally posted by scootz
Cheers guys. Electric motors are appearing on eBay now at sensible money - if only getting them to work outside the OE application meaningfully was easy (and at similarly sensible money!).


easy - just pick up a tesla as a donor and strip it ;-)


JC - 18/12/17 at 04:36 AM

Just don’t be around when one has a crash....lithium battery fires are not nice. I’ve seen the effects on aircraft......

Didn’t they say on Top Grand Tour Gear that the Lady Shave car Hammond crashed kept bursting into flames 5 days later?


907 - 18/12/17 at 07:41 AM

I sometimes feel a little nervous in a left lane when the right lane has one of those monstrous 4x4's in it. Roundabout, traffic lights etc.

A few blips on the throttle usually makes them aware of my presence.



I would not want an electric Seven, or any low sports car for that matter.

It would be like riding a super bike with no crash helmet.


Paul G


Sam_68 - 18/12/17 at 08:53 AM

Long before the Westfield iRacer pictured above, there was the WiSPER (Westfield in Structural Plastics Electric Roadster).

There are established companies who will sell you everything you need to convert a car to electric power, so IVA permitting, I don't see it as a big problem, as more advanced battery technology becomes available.

This company might be a good place to start: AVT

There are also dedicated forums for DIY EV enthusiasts, such as this one


swanny - 18/12/17 at 10:32 AM

http://www.dragonev.co.uk/

these guys turn up at kit car shows with a vindicator with electric motors.


Simon - 18/12/17 at 11:33 AM

Have a lookout for the wheeler dealer episode in the US about the electric maserati - goes into quite a lot of detail


Mr Whippy - 18/12/17 at 01:01 PM

While most electric converts seem to ignore the fact that their "clean" electricity is primarily produced by dirty coal, oil and nuclear power plants...

this is much more interesting and environmentally sound -

linky

run it on wood chippings and the net CO2 output/input is exactly the same, really your car is powered by the energy of the sun

ok it's a tad bulky but I think this looks so weird it looks good

would be great built onto the back of my Landy....


Sam_68 - 18/12/17 at 01:24 PM

quote:
Originally posted by Mr Whippy
While most electric converts seem to ignore the fact that their "clean" electricity is primarily produced by dirty coal, oil and nuclear power plants...


The picture is changing rapidly, though.

This year has seen both the first 'coal free' day of electricity generation in the UK, and also the first day when 'renewable' sources generated more than fossil fuel (oil, coal, gas).


peter030371 - 18/12/17 at 02:31 PM

Westfield are working hard at it still https://www.autocar.co.uk/car-news/anything-goes/westfield-build-new-mid-engined-%C2%A330k-sports-car-2018


jeffw - 18/12/17 at 02:41 PM

https://www.youtube.com/watch?v=WDu9HpPD8VY

https://www.youtube.com/watch?v=Rt4fGIoVMpM

More complicated than you might think


jeffw - 18/12/17 at 02:45 PM

https://www.youtube.com/watch?v=If09etyztl8


nick205 - 18/12/17 at 04:00 PM

Recently traveled in a Tesla taxi in Amsterdam. The driver/owner was not overly chuffed with it - "leccy Mondeo" - was his turn of phrase.

Whilst it was quiet you could sense fairly easily that pedestrians simply couldn't hear it - risky IMHO. Pedestrians are generally so tuned to hearing traffic as much as seeing it I do fear leccy cars present a hazard for people crossing a road.


bg0013 - 18/12/17 at 09:27 PM

https://www.morgan-motor.co.uk/ev3/

I think this is beautiful from morgan.

there is an electric radical racing in Australia that is quite rapid, but the battery and control technology are very expensive for the lap time.

im building a BEC at the moment, but the electric idea keeps popping up in the background, especially once you can get similar performance per kg economically.


coyoteboy - 19/12/17 at 01:47 AM

quote:
Originally posted by 907
I sometimes feel a little nervous in a left lane when the right lane has one of those monstrous 4x4's in it. Roundabout, traffic lights etc.

A few blips on the throttle usually makes them aware of my presence.



I would not want an electric Seven, or any low sports car for that matter.

It would be like riding a super bike with no crash helmet.


Paul G


As a giant 4x4 driver, I am already aware of your presence. The time that a low car is an issue or risks you being "missed" is on country lanes where you're lower than a hedge coming head on. At traffic lights, roundabouts etc you're just as visible as anyone else, if not more, from a higher vantage point


Sam_68 - 19/12/17 at 07:45 AM

quote:
Originally posted by Sam_68
quote:
Originally posted by coyoteboy
quote:
Originally posted by 907
I sometimes feel a little nervous in a left lane when the right lane has one of those monstrous 4x4's in it. Roundabout, traffic lights etc.

A few blips on the throttle usually makes them aware of my presence.

I would not want an electric Seven, or any low sports car for that matter.

It would be like riding a super bike with no crash helmet.

Paul G


As a giant 4x4 driver, I am already aware of your presence.

Me too, but if I wasn't, blipping your throttle wouldn't save you - my Range Rover is exceptionally well sound-insulated and my stereo is usually turned well up, to compensate for the fact that I'm as deaf as a post after donkey's years of driving aeroscreen'd kit cars!

I do find the reactionary comments on this thread quite amusing:

Battery safety: if electric cars had gained dominance first, can you imagine the wailing and gnashing of teeth if someone proposed a new power source that relied on a fragile tank of highly volatile fuel (which emits carcinogenic vapour when being refueled), in combination with an electrical system that's just waiting to produce sparks in an accident... and emits noxious and environmentally damaging gases as exhaust, to boot?

Pedestrian safety: much the same concerns resulted in laws demanding a man with a red flag walking in front of early cars. We got used to the transition from horses to cars, and I'm sure we'll get used to the transition from IC to EV.

If you're paying a such a lack of attention that you risk getting hit by an EV, the LCF's and MAMILS are gonna get you sooner or later anyway. If there is a sufficient uptick in road casualties as EV's are adopted en mass, it's not rocket science to fit them with some sort of noise generator.

It very much looks like EV's are going to gain dominance in the next few years, so we might as well get with the program?


nick205 - 19/12/17 at 09:25 AM

Sam_68

Point about fitting a noise generator noted and that may well be a solution.

Indeed if EV cars increase then pedestrians will find ways to adapt. Thinking further, what bothers me as much (if not more) is the number of people walking about with earphones on making hearing things less likely as well.

I think you're also right about trying to make a change from EV to IC - people don't always want to change easily (or without moaning).

I guess my point was to highlight a potential problem with the change from IC to EV. That said humans are quite adaptive and will no doubt cope with the change. Having potentially cleaner air to breathe seems a pretty strong argument for making the change


swanny - 19/12/17 at 01:06 PM

quote:
Originally posted by peter030371
Westfield are working hard at it still https://www.autocar.co.uk/car-news/anything-goes/westfield-build-new-mid-engined-%C2%A330k-sports-car-2018


Based on the GTM Libra. (though remains to be seen if it ever bears much resemblance when its done. They have been trying to buy a couple of cars to develop. They even did a bit of press in manchester last year with owners cars.


swanny - 19/12/17 at 01:09 PM

if everyone is plugged into a smart phone then they wont hear EV coming.
So you build collision avoidance apps into the phone surely?


russbost - 19/12/17 at 01:10 PM

quote:
Originally posted by scootz
Cheers guys. Electric motors are appearing on eBay now at sensible money - if only getting them to work outside the OE application meaningfully was easy (and at similarly sensible money!).


Does anyone have links to suitable motors at sensible money? I certainly can't find anything on Ebay, anything with any serious grunt is either fortunes, 3 phase, or both. I do recall a chat with Stig Mills some years back when he said that AC is much better than DC, but obviously you get losses translating from one to the other, but I wouldn't have thought we want 400V+ of 3 phase going around the car!

I do agree that there is going to be massive uptake of battery vehicles over the next few years, but I still haven't heard where all the material for batteries is going to come from (I don't believe there is enough Li on the planet, so we need an alternative), nor how we are going to cover not only our existing electricity usage, but the vastly increased requirements from all these battery vehicles, if we are trying to do this with solar & wind.
Also, might be a tiny hiccup if it's a cloudy windless day! :s
I have heard about global power hookups, ie, generate your solar in the desert & then "export" it, but don't see how that's going to work without far better collaboration between countries than we currently have

We seem to have largely given up with hydrogen power, but it's not stopped these guys LINK


nick205 - 19/12/17 at 02:23 PM

quote:
Originally posted by swanny
if everyone is plugged into a smart phone then they wont hear EV coming.
So you build collision avoidance apps into the phone surely?



Certainly an option.

Many cars have front/rear parking sensors which could possibly be used in this role when the car is travelling above say 5mph.


Sam_68 - 19/12/17 at 05:26 PM

quote:
Originally posted by nick205
Many cars have front/rear parking sensors which could possibly be used in this role when the car is travelling above say 5mph.


Much above 5mph, and EV's generate almost as much noise as IC cars, anyway.

We've got a good handful of EV's around where I live (mainly Teslas, with the odd I3) and being a rural area you can hear them in isolation. Surprisingly, it's very difficult to discern a difference between something like a Mercedes saloon and a Tesla when they're travelling at 30-40mph: almost all the noise they're making is tyre roar.

Bear in mind that at that speed an IC will often be cruising at not much more than tickover speed (maybe 1500rpm, max.). Unless it's accelerating hard, is exceptionally agricultural, or has a boy racer exhaust system, the engine will be operating very quietly.

The whole noise thing is a red herring, I reckon.


DW100 - 20/12/17 at 07:31 AM

Most of the motors used by car manufacturers are 3 phase.

You will have a converter to change incoming mains voltage to whatever the battery voltage is (200-800v DC)

Then a converter to turn the battery voltage to 3 phase for the motors and 12v for all the normal car stuff.


russbost - 20/12/17 at 08:20 AM

quote:
Originally posted by DW100
Most of the motors used by car manufacturers are 3 phase.

You will have a converter to change incoming mains voltage to whatever the battery voltage is (200-800v DC)

Then a converter to turn the battery voltage to 3 phase for the motors and 12v for all the normal car stuff.


So I assume this is the same in F1? That would explain radio instructions like - "stop the car & get out of it immediately" - it also makes more sense that I seem to remember there are some regulations, possibly in IVA, but may be elsewhere disallowing private builds of high voltage "kitcars" or one-offs - have I got that right?


scootz - 20/12/17 at 04:25 PM

quote:
Originally posted by russbost
Does anyone have links to suitable motors at sensible money?


I guess it depends on what you consider 'sensible'.

The pick is probably the BMW i3 engine. There's one on eBay for £3k or nearest offer. It has the range extender engine attached which you could remove and sell on to get some funds back. 170bhp and 250nm from a 50kg electric motor. Can't see any battery packs for sale though - makes me wonder if the breakers are prohibited from selling them(?).

Speaking of battery packs, the BMW one weighs over 200kg... I guess there has to be a penalty somewhere. I have no idea if the motor NEEDS all 200+ kg of those to operate, or whether you could get away for less in a low-weight project vehicle.

Then there's the anxiety of being the first to find out if BMW have locked them down in such a fashion that anyone other than an electronics engineer with unlimited access to associated technologies could make it run in anything other than an i3.

Also some Nissan and Renault motors out there - not as powerful though.


Sam_68 - 20/12/17 at 05:16 PM

quote:
Originally posted by russbost
... I seem to remember there are some regulations, possibly in IVA, but may be elsewhere disallowing private builds of high voltage "kitcars" or one-offs - have I got that right?

You can build electric 'kitcars' or one-offs, but the testing regime is in addition to IVA and is expensive.

The current Section 69 in the IVA manual demands that electric vehicles must have been mass produced to ECE R100, or has been individually tested to the same standard. Cost of individual testing to ECE R100 is circa £6-7K.


scootz - 20/12/17 at 05:26 PM

quote:
Originally posted by Sam_68
quote:
Originally posted by russbost
... I seem to remember there are some regulations, possibly in IVA, but may be elsewhere disallowing private builds of high voltage "kitcars" or one-offs - have I got that right?

You can build electric 'kitcars' or one-offs, but the testing regime is in addition to IVA and is expensive.

The current Section 69 in the IVA manual demands that electric vehicles must have been mass produced to ECE R100, or has been individually tested to the same standard. Cost of individual testing to ECE R100 is circa £6-7K.


£6-7k for testing... ouch!

Well, that'll be the end of that then - was just about to offer myself as a team guinea pig and stick an offer on the i3 motor as well.


scootz - 20/12/17 at 05:28 PM

However... what if it was a conversion on an already registered car from petrol to electric? Would the testing still be a requirement?


scudderfish - 20/12/17 at 05:39 PM

Provided you don't mod the chassis etc that would trip a re-IVA test, I don't see why not.


Sam_68 - 20/12/17 at 05:41 PM

quote:
Originally posted by scootz
However... what if it was a conversion on an already registered car from petrol to electric? Would the testing still be a requirement?


Yes, is my understanding.

ETA in response to Scudderfish's post: it is my understanding that VOSA has made clear that any vehicle having been converted will be subject to compliance, triggered by the application to change the fuel type on the V5 - regardless of any other alterations..

It's early days for EV's as part of the UK specialist car industry , of course, so it's possible that the regime may be made more flexible in the future (but don't bank on it).


[Edited on 20/12/17 by Sam_68]


scootz - 20/12/17 at 06:01 PM

Good info. Thanks.


UncleFista - 20/12/17 at 06:14 PM

If anyone is interested in how the national grid ratio of electricity differs between gas/coal/wind etc. in real time.

This link is great


gremlin1234 - 20/12/17 at 08:20 PM

quote:
Originally posted by Sam_68
quote:
Originally posted by russbost
... I seem to remember there are some regulations, possibly in IVA, but may be elsewhere disallowing private builds of high voltage "kitcars" or one-offs - have I got that right?

You can build electric 'kitcars' or one-offs, but the testing regime is in addition to IVA and is expensive.

The current Section 69 in the IVA manual demands that electric vehicles must have been mass produced to ECE R100, or has been individually tested to the same standard. Cost of individual testing to ECE R100 is circa £6-7K.


but secn 69 'Electric/Hybrid vehicles' is currently:

quote:
Section included for information only.
DVSA will carry out a visual inspection only as per General
Construction

and
quote:
69 Electric/Hybrid Vehicles – For information only


edit:
I suspect they will start allowing pre-approved 'modules' for battery, motor and controller


[Edited on 20/12/17 by gremlin1234]


Sam_68 - 20/12/17 at 09:54 PM

quote:
Originally posted by gremlin1234
I suspect they will start allowing pre-approved 'modules' for battery, motor and controller



Yes, I suspect you're right. And possibly even beyond that, if the will to keep IVA alive remains after Brexit.

I think at the moment it's a combination of them being caught on the hop by the sudden emergence of EV's as serious, mainstream vehicles, and lack of familiarity among their testing staff.

I'm no electrician, but when you actually read ECE R100 it in fact comes across as pretty straightforward. Once the testers start to become familiar with EV's, I don't think that it would be impossible to bring the key bits of ECE R100 within IVA, directly.

The pessimist in me says that it won't happen, because there isn't much of a will to retain IVA... the UK kit car industry is fading, and after Brexit the low volume manufacturers like Lotus, Ariel and Morgan will have to play by Europe's rules, or die, 'cos there isn't a big enough domestic market to sustain them.

But we digress...


Benzine - 21/12/17 at 12:11 AM

I'm building an electric trike at the moment to go through mSVA. Hope that 6k testing doesn't apply to mSVA or I'll just have to drive it round my drive


coyoteboy - 21/12/17 at 02:04 AM

quote:
Originally posted by swanny
if everyone is plugged into a smart phone then they wont hear EV coming.
So you build collision avoidance apps into the phone surely?


Agreed.

However deaf people have been not getting run over for years, and I've been cycling with headphones for about 2 decades without being almost hit due to not hearing. In both cases, you just compensate by actually looking, instead of assuming you'll hear stuff.

However even just walking round a city centre and you want to beat people to death for being totally unaware of their environment. I think really it's just a person thing - if you're that dozy, you'll get squashed.


David Jenkins - 21/12/17 at 12:37 PM

quote:
Originally posted by coyoteboy
However even just walking round a city centre and you want to beat people to death for being totally unaware of their environment. I think really it's just a person thing - if you're that dozy, you'll get squashed.


A year or so back my wife and I stopped off in Hong Kong, on our way to Australia. The roads and drivers there are scary and crossing them is hazardous, even when you're fully alert and looking around carefully. I couldn't believe the number of young women walking around with their eyes firmly fixed on their phones, even as they step out into the road. It was bad enough trying to avoid them when walking along the pavement!


hughpinder - 21/12/17 at 01:15 PM

So the BMW i3 motor weighs 50 kg, the tesla 100kwh battery is 183 kg, control gear 25kg? total 258 kg say?
Zetec+gearbox+ancilliaries 186kg, battery 10, fuel tank _ fuel _ pump 40kg , exhaust, radiator, fan 20- total 256kg - might not be that much in it overall!

I dont know how bulky th tesla battery is though.

Happy Christmas everyone,
Hugh


russbost - 21/12/17 at 01:26 PM

Unfortunately, if all you're going to be able to do is to modify an existing vehicle there's not a lot of point, as you can buy a 2nd hand Leaf with an owned battery for around £6-7k.

There are plenty of Prius batteries on Ebay for around £500 or so, but I seem to remember it has a pathetically low kWh rate?

There's one Leaf battery from 2015 car for £4500 Bargain or what - NOT!

I suppose if you are still allowed to modify an existing car then there's nothing to stop that from being an existing kitcar? .........


hughpinder - 21/12/17 at 01:56 PM

Prius battery = 1.31 kWh


hughpinder - 21/12/17 at 01:57 PM

Nissan Leaf about 24kWh


russbost - 21/12/17 at 03:05 PM

quote:
Originally posted by hughpinder
Prius battery = 1.31 kWh


So that would drive the BMW i3 motor flat out (127.5kW) for just over 30 seconds, I did say the Pious (misspelling intentional!) battery was pathetically tiny - I hadn't realised just how stupid it was! Might be useful for an electric pushbike, but not much else ...........

Presumably with any battery packs & motors coming from existing electric & hybrid vehicles, I'm guessing they probably all run at different voltages? Is there any standardisation?